Commit message: Reorganize and add more validation to MKL requantization

PiperOrigin-RevId: 387901341
Change-Id: I2515b9034c64e113db0bcec8337d30643ab0a0f1
CVE: CVE-2021-37665
CWE: CWE-20
Vulnerability description: TensorFlow is an end-to-end open source platform for machine learning. In affected versions due to incomplete validation in MKL implementation of requantization, an attacker can trigger undefined behavior via binding a reference to a null pointer or can access data outside the bounds of heap allocated arrays. The [implementation](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/core/kernels/mkl/mkl_requantization_range_per_channel_op.cc) does not validate the dimensions of the `input` tensor. A similar issue occurs in `MklRequantizePerChannelOp`. The [implementation](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/core/kernels/mkl/mkl_requantize_per_channel_op.cc) does not perform full validation for all the input arguments. We have patched the issue in GitHub commit 9e62869465573cb2d9b5053f1fa02a81fce21d69 and in the Github commit 203214568f5bc237603dbab6e1fd389f1572f5c9. The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, as these are also affected and still in supported range.

Project: tensorflow
File: mkl_requantize_per_channel_op.cc

  void Compute(OpKernelContext* ctx) override {
    try {
      const Tensor& input = ctx->input(kInputTensorIndex);
      const Tensor& input_min_vec = ctx->input(kInputMinVecIndex);
      float* input_min_vec_data = (float*)const_cast<void*>(
          static_cast<const void*>(input_min_vec.flat<float>().data()));
      const Tensor& input_max_vec = ctx->input(kInputMaxVecIndex);
      float* input_max_vec_data = (float*)const_cast<void*>(
          static_cast<const void*>(input_max_vec.flat<float>().data()));

      const Tensor& input_requested_min = ctx->input(this->kRequestMinIndex);
      const float input_requested_min_float =
          input_requested_min.flat<float>()(0);
      const Tensor& input_requested_max = ctx->input(this->kRequestMaxIndex);
      const float input_requested_max_float =
          input_requested_max.flat<float>()(0);

      size_t depth = input_min_vec.NumElements();
      OP_REQUIRES(
          ctx, input.dims() == 4,
          errors::InvalidArgument("Current RequantizePerChannel operator"
                                  "supports 4D tensors only."));
      OP_REQUIRES(
          ctx, input_min_vec.dim_size(0) == depth,
          errors::InvalidArgument("input_min has incorrect size, expected ",
                                  depth, " was ", input_min_vec.dim_size(0)));
      OP_REQUIRES(
          ctx, input_max_vec.dim_size(0) == depth,
          errors::InvalidArgument("input_max has incorrect size, expected ",
                                  depth, " was ", input_max_vec.dim_size(0)));

      if (out_type_ == DT_QINT8) DCHECK(input_requested_min_float < 0.0f);

      const float factor = (out_type_ == DT_QINT8) ? 127.0f : 255.0f;
      const float requested_min_max =
          std::max(std::abs(input_requested_min_float),
                   std::abs(input_requested_max_float));
      Tensor* output = nullptr;
      OP_REQUIRES_OK(ctx, ctx->allocate_output(kOutputTensorIndex,
                                               input.shape(), &output));

      std::vector<float> scales(depth);
      for (int i = 0; i < depth; ++i) {
        float min_max_from_vec = std::max(std::abs(input_min_vec_data[i]),
                                          std::abs(input_max_vec_data[i]));
        scales[i] = factor * (min_max_from_vec / requested_min_max /
                              static_cast<float>(1L << 31));
      }

      mkldnn::primitive_attr reorder_attr;
      reorder_attr.set_output_scales(2, scales);

      memory::dims dims_mkl_order =
          TFShapeToMklDnnDimsInNCHW(input.shape(), FORMAT_NHWC);
      memory::desc input_md = memory::desc(dims_mkl_order, MklDnnType<qint32>(),
                                           memory::format_tag::nhwc);
      memory::desc output_md =
          (out_type_ == DT_QINT8)
              ? memory::desc(dims_mkl_order, MklDnnType<qint8>(),
                             memory::format_tag::nhwc)
              : memory::desc(dims_mkl_order, MklDnnType<quint8>(),
                             memory::format_tag::nhwc);

      void* input_buf =
          static_cast<void*>(const_cast<qint32*>(input.flat<qint32>().data()));
      void* output_buf;
      if (out_type_ == DT_QINT8) {
        output_buf = static_cast<void*>(
            const_cast<qint8*>(output->flat<qint8>().data()));
      } else {
        output_buf = static_cast<void*>(
            const_cast<quint8*>(output->flat<quint8>().data()));
      }

      std::unique_ptr<memory> input_mem_prim(
          new memory(input_md, cpu_engine_, input_buf));
      std::unique_ptr<memory> output_mem_prim(
          new memory(output_md, cpu_engine_, output_buf));

      mkldnn::reorder::primitive_desc reorder_pd =
          ReorderPd(cpu_engine_, input_mem_prim->get_desc(), cpu_engine_,
                    output_mem_prim->get_desc(), reorder_attr);
      std::shared_ptr<stream> reorder_stream;
      MklDnnThreadPool eigen_tp(ctx);
      reorder_stream.reset(CreateStream(&eigen_tp, cpu_engine_));
      std::unordered_map<int, mkldnn::memory> reorder_args = {
          {MKLDNN_ARG_FROM, *input_mem_prim},
          {MKLDNN_ARG_TO, *output_mem_prim}};
      std::unique_ptr<mkldnn::primitive> reorder_prim(
          new mkldnn::reorder(reorder_pd));
      reorder_prim->execute(*reorder_stream, reorder_args);

      Tensor* output_min = nullptr;
      Tensor* output_max = nullptr;
      OP_REQUIRES_OK(ctx,
                     ctx->allocate_output(kOutputMinIndex, {}, &output_min));
      OP_REQUIRES_OK(ctx,
                     ctx->allocate_output(kOutputMaxIndex, {}, &output_max));

      output_min->flat<float>()(0) = input_requested_min_float;
      output_max->flat<float>()(0) = input_requested_max_float;
    } catch (mkldnn::error& e) {
      string error_msg = "Status: " + std::to_string(e.status) +
                         ", message: " + std::string(e.message) + ", in file " +
                         std::string(__FILE__) + ":" + std::to_string(__LINE__);
      OP_REQUIRES_OK(
          ctx, errors::Aborted("Operation received an exception:", error_msg));
    }
  }